Why Does Your Arm Hurt After You Get a Flu Shot?

Pornpak Khunatorn/iStock via Getty Images
Pornpak Khunatorn/iStock via Getty Images

If you’ve ever gotten a flu shot, you may have felt soreness in your upper arm for a day or two afterward. That’s just a sign the vaccine is working, immunologists say.

The flu vaccine works by introducing your body to a foreign substance called an antigen (in this case, the antigen is a deactivated or “dead” virus similar to the flu virus). Being exposed to an antigen “primes” immune system cells, preparing them to create antibodies should they ever encounter the foreign substance again [PDF]. The inactive virus in the vaccine can’t make you sick, but it does help sensitize your immune system to potential threats. Essentially, the vaccine puts your body on high alert for anything resembling the flu virus, enabling you to fight off infections and illnesses faster and more effectively than you could otherwise.

In the process of battling the inactive flu virus introduced by the flu vaccine, your immune system also releases mediators like histamine, which causes inflammation. In the event of infection, inflammation is important because it helps your body fight invaders and repair damaged tissue. But it’s also what causes soreness. The flu shot is usually injected into your upper arm, which is why the early immune response—and any pain—tends to be localized there.

Roughly one in five people have this type of painful reaction, immunologist Richard Zimmerman told Popular Science. If you’re susceptible to soreness after receiving a flu shot, there are a few steps you can take to alleviate the pain. Dr. Juanita Mora of the American Lung Association recommends taking an ibuprofen about two hours before getting the shot.

“You can also try icing the injection site to reduce redness and swelling,” Dr. Mora said.

It’s also important to move your arm around after receiving the shot so the vaccine isn’t quite so concentrated in one place. Barring that, you could always try getting the vaccine in your non-dominant arm so that any pain won’t interfere with your everyday activities.

Any pain is worth it, though: Even if you’ve never gotten the flu before, there’s always a chance you could get it in the future. And getting a flu shot also contributes to herd immunity, helping protect higher-risk populations (like children, older adults, and chronically ill individuals) who often can’t receive the flu vaccine for themselves. Keeping up-to-date on vaccines is one of the easiest ways individuals can contribute to community health.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

Why Do We Eat Pumpkin Pie at Thanksgiving?

gjohnstonphoto/iStock via Getty Images
gjohnstonphoto/iStock via Getty Images

While it’s possible—even probable—that pumpkins were served at the 1621 harvest festival that’s now considered the predecessor to Thanksgiving, attendees definitely didn’t dine on pumpkin pie (there was no butter or wheat flour to make crust).

The earliest known recipes for pumpkin pie actually come from 17th-century Europe. Pumpkins, like potatoes and tomatoes, were first introduced to Europe in the Columbian Exchange, but Europeans were more comfortable cooking with pumpkins because they were similar to their native gourds.

By the 18th century, however, Europeans on the whole lost interest in pumpkin pie. According to HowStuffWorks, Europeans began to prefer apple, pear, and quince pies, which they perceived as more sophisticated. But at the same time pumpkin pie was losing favor in Europe, it was gaining true staple status in America.

In 1796, Amelia Simmons published American Cookery, the first cookbook written and published in the New World colonies. Simmons included two recipes for “pompkin pudding” cooked in pastry crust. Simmons’s recipes call for “stewed and strained” pumpkin, combined with a mixture of nutmeg, allspice, and ginger (yes, it seems our pumpkin spice obsession dates back to at least the 1500s).

But how did pumpkin pie become so irrevocably tied with the Thanksgiving holiday? That has everything to do with Sarah Josepha Hale, a New Hampshire-born writer and editor who is often called the “Godmother of Thanksgiving.” In her 1827 abolitionist novel Northwood, Hale described a Thanksgiving meal complete with “fried chicken floating in gravy,” broiled ham, wheat bread, cranberry sauce, and—of course—pumpkin pie. For more than 30 years, Hale advocated for Thanksgiving to become a national holiday, writing regular editorials and sending letters to five American presidents. Thanksgiving was a symbol for unity in an increasingly divided country, she argued [PDF].

Abraham Lincoln eventually declared Thanksgiving a national holiday in 1863 (to near-immediate outcry from Southerners, who viewed the holiday as an attempt to enforce Yankee values). Southern governors reluctantly complied with the presidential proclamation, but cooks in the South developed their own unique regional traditions. In the South, sweet potato pie quickly became more popular than New England’s pumpkin pie (mostly because sweet potatoes were easier to come by than pumpkins). Now, pumpkin pie reigns supreme as the most popular holiday pie across most of the United States, although the Northeast prefers apple and the South is split between apple and pecan, another Southern staple.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

What's the Difference Between Stuffing and Dressing?

iStock
iStock

For carbohydrate lovers, nothing completes a Thanksgiving meal quite like stuffing—shovelfuls of bread, celery, mushrooms, and other ingredients that complement all of that turkey protein.

Some people don’t say stuffing, though. They say dressing. In these calamitous times, knowing how to properly refer to the giant glob of insulin-spiking bread seems necessary. So what's the difference?

Let’s dismiss one theory off the bat: Dressing and stuffing do not correlate with how the side dish is prepared. A turkey can be stuffed with dressing, and stuffing can be served in a casserole dish. Whether it’s ever seen the inside of a bird is irrelevant, and anyone who tells you otherwise is wrong and should be met with suspicion, if not outright derision.

The terms are actually separated due to regional dialects. Dressing seems to be the favored descriptor for southern states like Mississippi, Tennessee, South Carolina, and Georgia, while stuffing is preferred by Maine, New York, and other northern areas. (Some parts of Pennsylvania call it filling, which is a bit too on the nose, but to each their own.)

If stuffing stemmed from the common practice of filling a turkey with carbs, why the division? According to HuffPost, it may have been because Southerners considered the word stuffing impolite, and therefore never embraced it.

While you should experience no material difference in asking for stuffing or dressing, when visiting relatives it might be helpful to keep to their regionally-preferred word to avoid confusion. Enjoy stuffing yourselves.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

SECTIONS

arrow
LIVE SMARTER